Because of recent reports about phosphine resistance problem, development of effective fumigation method to control grain pests became very important. In this study, a chemical treatment, ethyl formate fumigant treatment, and a physical treatment, atmospheric control, were attempted as alternative solutions to this problem. In this study, for CA(Controlled atmosphere) treatment, 99.999% nitrogen was used to create a hypoxic condition with less than 5% oxygen, and for EF, the treatment concentration was 10 mg/L to 80 mg/L. As a result of the study, in CA single treatment, adult insects showed a mortality rate of less than 10% even after 2 weeks of treatment, and pupae and larvae showed a mortality rate 71% and 34%, but eggs showed a mortality rate of 100%. In EF single treatment, adults and larvae showed a 100% mortality rate at 80 mg/L, but eggs showed a 50% mortality rate and pupae were not affected. Considering the results, CA single treatment is not suitable for controlling Tribolium castaneum because of long treatment period, and in the case of EF single treatment, additional researches on longer treatment time is needed.

This study was conducted to investigate the quality of kimchi cabbages stored under a pallet unit-controlled atmosphere (PUCA), containing 2% O2 and 5% CO2, and to develop quality prediction models for cabbages stored under such conditions. Summer and winter cabbage samples were divided into PUCA-exposed groups and atmospheric airexposed control groups (in a cold storage). The control summer cabbages lost up to 8.31% of their weight, whereas the PUCA-exposed summer cabbages lost only 1.23% of their weight. Additionally, PUCA storage effectively delayed the reduction in cabbage moisture content compared with the control storage. After storage for 60 and 120 days of the summer and winter samples, respectively, the reducing sugar contents were higher in the PUCA groups than in the control groups. The linear regression analysis-derived equations for predicting the storage period, weight loss, and moisture content in the control groups, as well as those for predicting the storage period and weight loss in the PUCA groups, were appropriate according to the adjusted coefficient of determination, root mean square error, accuracy factor, and bias factor values. Therefore, this PUCA system would be useful for improving the shelf life of the postharvest summer and winter cabbages used in the commercial kimchi industry.

In this study, a controlled atmosphere (CA) storage system is proposed as a storage method for prolonging processing period. Persimmon was placed in CA storage at 0.5oC±0.5 for 92 d. The qualities of the stored persimmons were compared to determine the possibility of extending shelf life. ‘Sangjudungsi,’ which was harvested on October 26, 2017, was applied to the persimmons. In order to compare differences according to size, the persimmons were classified into Size No. 2 (170 g) and Size No. 3 (145 g). In the result, the yellowness of CA-stored persimmons was 26.3% lower than that of cold-stored ones, confirming that after-ripening was delayed. The firmness of CAstored and Size No. 3 persimmon was higher than that of cold-stored and Size No. 2 persimmon. Tannin decreased significantly in cold storage, but it tended to increase in CA storage. The sugar content of Size No. 3 was lower than that of Size No. 2, but there was no difference in tendencies according to the storage method. Weight loss in CA storage was lower than that in cold storage. A comparison of color difference, firmness, sugar content, tannin, and weight loss ratio showed that CA storage was more effective in improving shelf life than cold storage.

The O2 and CO2 concentrations in controlled atmosphere (CA) rooms are determined by the respiration of produce like apples and the airtightness of the CA room, with gas in the CA room controlled by O2 and CO2 removal as well as respiration (CO2 increase and O2 decrease). The purpose of this study was to evaluate the validity of the gas exchange model for O2 removal, CO2 removal, the rate of O2 decrease and CO2 increase by respiration of apples, and airtightness of the CA room. It took 17.5 hours to reduce O2 concentration from 20.9% to 2.0% after loading 4.3 tons of Fuji apples into the CA room, which was 4.2 hours longer than the 13.3 hours of the model formula. After the CO2 concentration rose to 0.5% due to respiration, it took 4.7 hours to lower the CO2 concentration to 0.2%, which was 0.6 hours longer than that of the model equation. The rate of CO2 increase by respiration was 0.021%/ h, which was similar to the model equation (0.017%/h). Also after 4.7 hours, the O2 concentration decreased by 0.1% which was also in line with the model equation (0.13%/h).

This study was conducted to propose the conditions of controlled atmosphere (CA) storage suitable for the storage of winter Chinese cabbage and to investigate the maximum storage period of Chinese cabbage based on the results of the quality analysis for CA storage. The weight loss rate of Chinese cabbage stored at 194 days in low temperature storage was about 2 times higher than that in CA storage. The trimming loss rate of Chinese cabbage stored at low temperature was 1.5 times higher than that of CA storage after 83 days of storage. Bolting of Chinese cabbage was observed in only low temperature storage. The Chinese cabbage firmness of CA storage was not different in the range of 5.7-6.2 N, while low temperature storage gradually increased after 83 days of storage and was 7.5 N at 194 days. The incidence of mold occurred after 83 days in low temperature storage, while in CA storage it occurred after 153 days. In the quality evaluation, CA storage for Chinese cabbage was rated 1.5-1.9 points higher than the low temperature storage. The maximum storage period of Chinese cabbage at low temperature storage was 83 days and that at CA storage 153 days.

본 연구에서는 현장에서 필요한 겨울배추 CA저장에 적합한 조건을 제시하고, 저온 저장한 배추와의 품질 및 저장 기간을 비교 분석하여 겨울배추의 최대 저장 가능기간을 제시하고자 본 연구를 수행하였다. 겨울배추 CA저장의 저장 조건은 0°C, 90-95%, O2 1.0-3.0%, CO2 0.2-5.0%로 최종 설정하였으며, 저온저장고와 CA저장고에 예건한 겨울배추를 각각 1.8 ton, 1.0 ton 입고하였다. 품질조사 항목은 중량감모율, 정선손실율, 경도, 곰팡이 발생율, 관능검사이며, 품질조사는 입고 후 0일, 52일, 83일, 153일, 194일차에 진행하였다. 194일 저온 저장한 배추의 중량감모율은 CA저장한 배추보다 약 2배정도 높았으며, 정선손실율도 저온저장이 CA저장보다 1.5배 많았으며, 저장 83일 이후부터 배추 내부의 추대현상이 저온저장에서 많이 관찰되었다. 경도의 경우 CA저장 배추는 5.7 - 6.2 N범위에서 큰 변화를 보이지 않은 반면, 저온저장 배추는 83일 이후부터 점차 증가하는 모습을 보여 194일에 7.5 N을 가졌다. 곰팡이 발생율의 경우 저온저장 배추는 83일 이후 발생하기 시작하였으며, CA저장 배추는 153일 이후 발생하여 70일 정도 곰팡이 발생을 지연시켰다는 것을 알 수 있었다. 관능검사의 경우 CA저장이 전반적인 평가항목에서 저온저장보다 1.5 - 1.9점 높게 평가되었다. 겨울 배추의 최대 저장기간은 저온저장이 83일, CA저장이 153일로 CA저장이 저온저장보다 약 1.9배 더 장기간 저장이 가능한 것으로 나타났다.

This study was carried out to indirectly predict the storage time limit, hardness, and acidity of Fuji apples in controlled atmosphere (CA) storage. A sensor installed inside the CA storage measured temperature, relative humidity, and gas composition data in real time. The respiration rate from five tons of apples in CA storage was calculated to predict the weight loss rate. As a result, the predicted and actual weight loss rate induced a predictable residual storage time equation that showed a significantly high correlation. The apple storage period showed a high reliability (R2=0.9322) because the predicted equation using respiration rate and number of days stored was about nine months for five tons of apples. Furthermore, the hardness and acidity prediction equation were derived from the quality analysis. However, there was not enough analysis sample correlation (the coefficient was as low as 0.3506 and 0.3144, respectively), but the tendency could be confirmed by reduced hardness and acidity. As a result, these quality prediction equations could encourage CA container distribution, effective for agricultural shipment regulation and increasing the ease of operations.

This study was conducted to develop and evaluate an appropriate control device for a purge type controlled atmosphere (CA) storage in Korea. To determine ideal performance, oxygen and carbon dioxide control capability and airtightness were analyzed according to the postharvest management manual of CA storage of Fuji apples. In shortened experiments for CA storage, the condition was delayed CA at 0-0.5oC for three days and stored at 0.1-0.5% carbon dioxide levels for 3 days and then further stored 6 days under 1% carbon dioxide. As a result, the temperature control range of a developed CA container was 0.0-0.5oC, and the relative humidity was more than 90%, except for the defrosting step for the freezer during the storage period. The rate of pressure reduction for the CA container in the negative and positive pressure states was 0.45 and 0.21 mmH2O/min, respectively, and it was twofolds higher than standard airtightness for CA storage. After nitrogen injection, oxygen concentration was achieved at 2%, and carbon dioxide concentration was maintained at 0.1-0.5% for 6 days. Afterwards, carbon dioxide levels were tightly controlled between 0.1-1.0%. These results suggest that a developed purge type CA container could be effective in commercially maintaining the quality of agricultural products.

This study was conducted to develop the domestic production of a controlled atmosphere (CA) storage system, including nitrogen generator and carbon dioxide eliminator using selective gas separation membrane and operating program. Generally, the gas composition inside general cold stores constantly changes due to the metabolic activity of the respiring vegetables and fruits and leakage of gases through doors and walls. However, the CA container developed by our research team is able to control of the level of oxygen and carbon dioxide inside the reefer, making it simple and effective in operation. The efficiency of the nitrogen generator to replace oxygen with nitrogen inside the CA container was approximately 1.33% per hour. The change in oxygen concentration inside the CA container during the operation refrigerator almost did not show any difference for 8 days. Therefore, CA storage container should be a promising approach to maintaining the high quality of agricultural products during storage.

국내 사과를 외국으로 수출하기 위해서는 수입국의 검역 대상 해충을 완전히 제거하는 것이 필수적이다. 이를 위한 수확 후 해충 사멸 기술 로서 환경조절열처리(controlled atmosphere and temperature treatment system: CATTS) 기술이 개발되고 있다. 본 연구는 상이한 가해 습 성으로 사과 과실에 피해를 주는 두 해충에 대해 CATTS의 사멸조건을 결정하였다. 사과애모무늬잎말이나방(Adoxophyes paraorana)은 사과 과 실 표면을 가해하는 해충인 반면 복숭아명나방(Dichocrocis punctiferalis)은 과실의 내부를 가해한다. 여러 가해 발육태 가운데 두 곤충 모두 5령 유충이 열에 대한 내성이 가장 높았다. 고농도(15%)의 이산화탄소, 저농도(1%) 산소 및 46℃ 온도 조건에서 1 시간 동안 처리하는 CATTS 처리 조건은 사과애모무늬잎말이나방 5령 유충을 100% 사멸시켰다. 그러나 동일한 CATTS 조건에서 복숭아명나방 5령 유충은 88%의 사멸 효과를 보였으며, 100% 사멸 효과를 나타내기 위해서는 2 시간의 열처리를 요구했다. 이를 바탕으로 사과를 가해하고 있는 두 종의 5령 유충 3,000 마리 이상에 대해서 각각 CATTS 처리 효과를 확증하였다. 본 연구는 완전 사멸을 위해서는 심식충이 비심식충에 비해 장기간 CATTS 처리가 요구 된다는 것을 보여 주었다.

Postharvest insect pest control is highly demanding in agricultural industry including domestic consumer markets and exporting products for a quarantine purpose. Especially, the organic or environmentally friendly agricultural products do not fit to the traditional chemical postharvest treatments using methyl bromide (MeBr) or phosphine (PH3). As an alternative, a physical treatment called CATTS (controlled atmosphere and temperature treatment) has been developed to control various insect and mite pests on ornamental products. The oriental fruit moth, Grapholita molesta, infects the apple or pear fruits and is limited in importing and exporting the infected products. To apply CATTS on this insect pests, the most heat-tolerant stage was determined. Among the immature stages locating on the fruits, the fifth instar larvae were the most tolerant to 44℃ for 20 min. A ramping step of CATTS is to increase chamber temperature from 25℃ to 46℃ under 15% CO2 and less than 1% O2. The ramping rate was positively correlated with the CATTS efficiency. After the ramping step, the duration of CATTS was positively correlated with CATTS efficiency. However, fruit damage by CATTS was negatively correlated with the ramping rate was positively correlated with the CATTS duration. in addition, the CATTS efficiency was highly dependent on the fruit internal temperature at 44℃. From all these parameters, we developed a standard protocol yielding 100% control efficiency of CATTS.

본 연구애서는 ‘후지’ 사과의 CA 저장을 실용화하기 위하여 수확시기와 일정기간 저온저장한 후 CA 환경을 설정하는 지연 CA 처리가 저장 중 내부갈변장해와 과실품질에 미치는 영향을 조사하였다. 1차 년도에 ‘후지’ 사과를 10월 22일에 수확하였을 때 밀병 발생율이 40% 였고, CA 환경 조성(O2 2.5 ± 0.5% + CO2 2.5 ± 0.5%)을 20일 지연 CA 저장하였을 때는 내부갈변이 발생하였으나, 30일 지연 CA 저장에서는 내부갈변이 발생하지 않았다. 2차 년도에는 수확시기가 늦어질수록 밀병 발생율이 높았고, 이러한 과실은 10~30일 지연 CA 처리구에서 내부갈변장해가 발생하였으나, 40일 지연 CA 처리구 에서는 내부갈변장해가 발생하지 않았다. 호흡량은 저온 저장 과실에서는 저장기간이 길어질수록 급격히 증가하였으나 지연 CA 저장에서는 호흡량이 낮게 유지되었고, 급속 CA 저장에 비해서 차이를 보이지 않았다. 에틸렌 발생량은 지연 CA 저장한 과실들이 저온저장에 비해서 낮았으나, 급속 CA 저장에 비해서는 다소 높은 발생량을 보였다. 산함량은 지연 CA 저장이 급속 CA 저장에 비해 저장기간이 길어질수록 감소하는 경향이었고, 경도는 저장 8개월 후에도 급속 CA 처리구와 지연 CA 처리구간에는 차이를 보이지 않았다.

 ,  , The hawthorn spider mite, Tetranychus viennensis, is a pest of apples and a quarantine pest from some countries that import apples from Korea. A controlled atmosphere and temperature treatment system (CATTS) was developed as an alternative disinfestation method to methyl bromide fumigation treatment, and has been applied to control various insects and other arthropod pests on fruits. We applied CATTS to disinfect T. viennensis under conditions that were previously developed to control the peach fruit moth, Carposina sasakii. First, T. viennensis was sampled from Japanese apricot, Prunus mume, and identified by its morphological characters. In addition, both cytochrome oxidase I (COI) and internal transcribed spacer (ITS) sequences supported the morphological identification. Second, the heat-tolerant developmental stage was determined in T. viennensis. When a 46℃ heat treatment was applied to egg, nymph, and adult stages of T. viennensis, adults were the most tolerant stage. Third, when heat temperature was used along with 1% O<, SUB>, 2<, /SUB>, and 15% CO<, SUB>, 2<, /SUB>, , the mites showed a significant increase in susceptibility to the heat treatment. Finally, CATTS at 46℃ with 15% CO<, SUB>, 2<, /SUB>, and 1% O<, SUB>, 2<, /SUB>, for 30 min resulted in 100% mortality of all T. viennensis development stages. These results indicated that CATTS isapplicable to disinfest T. viennensis in post-harvest apples.

The quality properties of peeled ginger (PG) were investigated during CA storage at different CO₂concentrations. O₂ concentration was kept constant at 5% while CO₂of 6%, 14%, 22% and 30% were used. It was found that the weight loss rate tended to decrease with an increase of CO₂. In the case of fixed 10 ℃ storage, the Lvalue and a-value of the exterior color in treatment increased more than that of control with respect to time, while the b-value of the exterior color and the cutting plane color showed no significant difference. In the exterior color, the results of PG-25 ℃ showed similar with PG-10 ℃ except b-value of the exterior color which showed not a little change. The cutting plane color did not showed significantly difference in the PG samples between 25 ℃ and 10 ℃ . Hardness of the PG during storage was found to decrease most severely at 6% of CO₂concentration regardless of storage temperature. The growth of microorganisms during storage of the PG tended to be restrained as CO₂concentration increased. However, microorganisms, when maintained at 25 ℃ storage, multiplied rapidly to 10^8 CFU/g within 4 days regardless of concentration.

The microstructure and mechanical property of hot-pressed nanocomposites with a different temperature for atmosphere changing from to Ar have been studied. When the atmosphere changed from to Ar gas at , the hot-pressed composite was characterized by inhomogeneous microstructure and low fracture strength. On the contrary, when the atmosphere changed at a lower temperature of , a more homogeneous microstructure and higher fracture strength was observed.

The formation, microstructure and properties of novel ceramic composite materials manufactured by active-filler-controlled polymer pyrolysis were investigated. In the presence of active filler particles such as transition metals, bulk components of various geometry could be fabricated from siliconorganic polymer. Molybdenum- and tungsten-filled polymer suspensions were prepared and their conversion to ceramic composites by annealing in atmosphere were studied. Dimensional change. porosity and phase distribution (filler network) were analyzed and correlated to the resulting hardness values. Molybdenum and tungsten as active filler were carburized completely to , and WC in atmosphere. Consequently, microcrystalline composites with the filler reaction products embedded in a silicon oxycarbide glass matrix were formed. Hardness was increased with increasing carburization and reached 8.6-9.5 GPa in the specimen pyrolyzed in atmosphere.

This study was conducted to investigate the change in the quality of early season Fuji apples that were subjected to eight different storage conditions using the developed controlled atmosphere (CA) storage system. Early season Fuji apples grown at Mungyeong, in the South Korea, were harvested in September 2014 for storage studies. Flesh firmness, titratable acidity, total soluble solid content, weight loss, and internal browning disorder were used as quality indicators for the stored apples. Flesh firmness and weight loss were better than that of the control after 70 days of storage. However, there was no significant difference in the titratable acidity or total soluble solid content among the apple samples from eight chambers after storage. The internal browning disorder of apple samples in CA chambers occurred when exposed to 1% CO2+2% O2 and 1% CO2+0.5% O2, resulting in a higher incidence rate of 2 and 8% after 70 days of storage than that in the control. In addition, the CA storage conditions at 3, 4 and 5% CO2+2% O2 increased the rate of internal browning disorder by 26%. Therefore, CA storage can be used to maintain the quality of the apple if the optimal gas concentrations in the CA are applied to the storage strategy.